If so, most physicians would administer anywhere between 600 mg to 1200 mg twice a day for a total of 4 doses. This is based on the following trial: J Am Coll Cardiol 2002;40:298-303. In this study, the investigators found that the higher dose of mucomyst (1200 mg BID) had a statistically significant effect at lowering rates of contrast-induced nephropathy when the patient was receiving high doses of contrast (> 140 ml). Keep in mind that:

the patients had an eGFR of less than 60

all the patients received IVF (in this case, 0.45% NaCl

I think the better way to protect against contrast-induced nephropathy would be to administer IVF's rather than focus on the dosing of mucomyst.